Check out Double decker Free 3D model on CGTrader for free. High-quality mesh by dave-sutton.
STL (Stereolithography, filesize: 450 KB), OBJ (OBJ, filesize: 363 KB), 3DS (3D Studio, filesize: 323 KB), DAE (Collada, filesize: 1.11 MB), FBX (Autodesk FBX, filesize: 918 KB), IGE (IGES, filesize: 299 Bytes), MAX (Autodesk 3ds Max, filesize: 904 KB), SKP (Sketchup, filesize: 1.01 MB), OTHER (Other, filesize: 291 KB)